A long time ago in a valley far far away there existed a great civilization, known to archaeologists as the Indus Valley Civilization, located in what is today Pakistan and northern India. They did wondrous things, and had highly developed cities in which many houses had individual wells, bathrooms, and an elaborate underground drainage system. The social conditions for their
citizens was superior to those of Egyptians or Babylonians of the time. Life was good.
But around 3800 years ago it all started to fall apart, and until recently no one really understood why. The basics of civilisation crumbled – their standardized system of weights and measures used for trade and taxation fell our of use, as was their unique writing system. Trading links with the Near East were broken. An invasion by Aryan people from India, or a flooding of the Saraswati River, destroying the agricultural system, have both been hypothesized as possible causes.
Now a study of precipitation records from Holocene sediments in an ancient lake in northern India has shown that a major drought event occurred in the area 4100-3900 years ago, linked to a weakening of the annual Indian summer monsoon. Although not conclusive proof, it seems that this had a severe impact on agriculture in the region, which in turn put such a strain on this early urban civilization that it eventually collapsed.
Of course we hope that our own civilization is robust enough to withstand such changes in the weather, that our global transportation systems will allow us to switch food sources, and that there won't be droughts everywhere at the same time. But its yet another sobering reminder of how quickly climate changes can happen and of the inevitability of the consequences (a polite way of saying that if the annual rains fail for a decade, so will the crops, and so will the people who depend on them).
Source: http://geology.geoscienceworld.org/content/42/4/339.full
citizens was superior to those of Egyptians or Babylonians of the time. Life was good.
But around 3800 years ago it all started to fall apart, and until recently no one really understood why. The basics of civilisation crumbled – their standardized system of weights and measures used for trade and taxation fell our of use, as was their unique writing system. Trading links with the Near East were broken. An invasion by Aryan people from India, or a flooding of the Saraswati River, destroying the agricultural system, have both been hypothesized as possible causes.
Now a study of precipitation records from Holocene sediments in an ancient lake in northern India has shown that a major drought event occurred in the area 4100-3900 years ago, linked to a weakening of the annual Indian summer monsoon. Although not conclusive proof, it seems that this had a severe impact on agriculture in the region, which in turn put such a strain on this early urban civilization that it eventually collapsed.
Of course we hope that our own civilization is robust enough to withstand such changes in the weather, that our global transportation systems will allow us to switch food sources, and that there won't be droughts everywhere at the same time. But its yet another sobering reminder of how quickly climate changes can happen and of the inevitability of the consequences (a polite way of saying that if the annual rains fail for a decade, so will the crops, and so will the people who depend on them).
Source: http://geology.geoscienceworld.org/content/42/4/339.full